Resilient sealing strips for sealing doors



June 12, 1962 E. P. HARRIS RESILIENT SEALING STRIPS FOR SEALING DOORS Filed Nov. 13, 19 56 3 Sheets-Sheet 1 alga.

INVENTOR. 0 WARD FHA RR/s BY ATTORNEY June 12, 1962 E. P. HARRIS 3,038,217

RESILIENT SEALING STRIPS FOR SEALING DOORS Filed Nov. 15. 1956 3 Sheets-Sheet 2 INVEN TOR. E0 WARD Pf/mele/s ATTORNEY June 12, 1962 RESILIENT SEALING STRIPS FOR S EALING DOORS INVENTOR.

EDWARD Pfi/l/Pla/s BY ATTORNEY E. P. HARRIS 3,038,217

Uited States Patent Ofilice 3,638,217 Patented June 12, 1962 3,038,217 RESILENT SEALING STRIPS FUR SEALING DGORS Edward I. Harris, Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Filed Nov. 13, I956, Ser. No. 621,838 2 Claims. (Cl. 20-69) This invention relates to sealing strips suitable for sealing doors and the like, and in particular to a method of making sealing strips and apparatus therefor.

Among the various types of sealing strips in prevalent use in connection with doors and the like are those which consist of an elongated flexible rubber-like tubular member filled with a low density more or less resilient, strip material. One form of this type is designed for use in applications which involve relatively low pressure for holding a door in sealing contact with the seal, as for example, a door held in a closed position by magnetic means. It includes a relatively heavy flat base portion and a relatively thin and highly flexible bulb or tubular portion of substantial width, which is filled with a mildly resilient, compressible strip, or batt, of fibrous material such as Fiberglas or a low density elastomeric foam. The base portion of the seal provides it with a satisfactory degree of structural rigidity and means whereby the seal may be secured to a door frame or the like, while the highly flexible nature of the bulb portion and the filler material permits it to be readily deformed and thereby provide sealing contact with the door over substantially the width of the seal.

Among the objects of this invention is to provide an economical and efficient method of continuously stuffing or filling the tubular or bulb portion of a sealing strip of the type described, with a continuous strip of compressible, resilient material and apparatus for performing the process. In general, the method involves first extruding or otherwise forming a seal strip member of heat scalable rubber-like material which includes a relatively flat base portion of substantial thickness having a bulb portion integrally formed therewith, wherein the base portion forms a wall or" the bulb portion. Next, the base portion is slit or otherwise progressively opened longitudinally thereof and a suitable strip of filler material is fed into the opened cavity of the bulb as it is being opened. Finally, the slitted edges are rejoined by heat sealing or other suitable means. The invention further involves apparatus for sequentially opening the seal base, filling the bulb cavity with a filler strip and heat sealing the opened base edges, in a continuous operation. In other embodiments, the seal strip is extruded in a form wherein the base portion of the seal is open and the edges of the opening or seam are provided with a positive lock means to close the base, the seam then being preferably sealed.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein preferred embodiments of the present invention are clearly shown.

In the drawings:

FIGURE 1 shows an elevational cross sectional view of an extruded seal member.

FIGURE 2 is another form of an extruded seal member.

FIGURE 3 is one form of apparatus which may be used for continuously filling the seal member shown in FIGURE 1 with a compressible filler strip.

4-4 of FIGURE 3.

FIGURE 5 is a cross sectional view taken along line 55 of FIGURE 3.

FIGURE 6 is another form of apparatus for filling bulb type seals with a filler strip.

FIGURE 7 is a cross sectional view of a seal member which may be filled with a filler using the apparatus of FIGURE 6.

FIGURE 8 is a cross sectional view taken along lines 88 of FIGURE 6.

FIGURE 9 is a cross sectional view taken along line 99 of FIGURE 6.

#FIGURE 10 is another view of the apparatus shown in FIGURE 6 which does not have a seal strip associated therewith.

The invention will now be described in greater detail in reference to the drawings.

FIGURE 1 shows a cross sectional view of an extruded elongated seal strip body particularly designed to be filled with a strip of compressible filler material in accordance with the present invention. It includes a relatively heavy base portion ll) having a relatively thin walled bulb or tubular portion 12 integrally formed therewith, the base It forming a wall of the bulb. The base 10 has downwardly projecting generally L-shaped portion 14 extending along the length of the base and forming an L-shaped groove 15, which serves as a means for sealingly securing the base of the seal to a door frame or the like in a manner well known in the art. The base 10 is also provided with an extension 16 projecting laterally beyond the outer boundary of the bulb 12. The seal strip is further provided with a generally Z-shaped slit 18 splitting the base 10 excgpt for a thin web 20 and defining a groove or offset 22 in the base extension 16, and a lip or tongue 24 integrally attached to the base 19 and receivable in the groove 22. It will be noted that the Z-shaped character of the slit provides a V-shaped recess 26 which receives a V-shaped projection 28, the apex of which is directly somewhat inwardly of the base It), to properly position the seal parts in a sealed or closed relation as will be hereinafter described. The seal strip as shown in FIGURE 1 is preferably extruded from a heat sealable synthetic resin of the vinyl type which permits the formation of a self-sustaining highly flexible relatively thin rubber-like bulb portion 12.

Another form of sealing strip member which may advantageously be used in the present invention is shown in cross section in FIGURE 2 in extruded form. It differs from the seal strip shown in FIGURE 1 in that tongue or lip portion 24A is provided with a projecting, preferably longitudinal, diamond-shaped wedge 30 integrally attached thereto, and the offset portion 22A of the base extension 16A is provided with a corresponding diamond-shaped longitudinal recess 32, for receiving the wedge 34 in interlocked relation. The base of the strip 10A adjacent the tongue 24A is provided with a vertical wall 34 which serves to guide the vertical wall 36 in the filler filling operation as will be hereinafter apparent. In extruded form, the walls 34 and 36 are joined by a thin web 35 to facilitate extrusion and handling of the strip.

In filling the seal strip as, for example, the strip shown in FIGURE 1, with a compressible filler strip in accordance with the present invention, apparatus shown in FIGURE 3 may be advantageously used. It includes a base plate 37 having a longitudinal seal supporting member 38 adapted to slidingly support the seal base 10. A knife blade 39, or other suitable means, attached to base plate 37, is provided to slit or tear the web 20 of the seal body to open the seal body bulb as the seal body passes thereacross from left to right. Immediately ahead of the knife blade 39 is a guide member 40 supported on an inverted U-shaped housing member 41, diverging from the horizontal plane of the seal extension 16 and being operative to raise the extension 16 to permit a strip of compressible material 42 to be laid on the base 10 of the seal body (as shown in FIGURE 4) through an opening in the housing 41 guided therein by a funnel 43 supported by the housing member 41 as shown. Ahead of the funnel 43 is a second guide member 44 operative to depress the bulb 12 and extension 16 to its closed position. Finally, ahead of the guide plate 44 are a pair of opposed rollers 45 and 46 electrically connected to a high frequency source 47 operative to force the tongue 24 into offset 22 and heat seal the parts together as shown in FIGURE for reforming the bulb portion into an integrated structure. It will be noted that the V-shaped recess 26 and the V-shaped projection 28 are directed inwardly of the seal base to permit the pressure of the rollers 45 and 46 to tend to force the coopcrating tongue 24 and extension 16 in a mechanically interlocked relation.

The rollers 45 and 46 may be of any suitable material, preferably metal, and are preferably cylindrical in shape. The rollers are preferably mounted for adjustment relative to each other. Any suitable means such as mechanical or hydraulic pressure, etc., may be utilized. The rollers 45 and 46 are shown connected as electrodes in the output circuit of an oscillator contained in the high frequency unit 47, in such a fashion that oscillating high frequency waves generated in the oscillator coils will alternate between the rollers so as to pass through the portions 16 and 24 of the seal body which are pressed together between the rollers to heat seal these portions together as is well known in the art. In place of the roller means 45 and 46, equivalent induction heat sealing means may be utilized as is well known in the art as, for example, a pair of opposed endless metal belts or bar sealing apparatus. a

The above described apparatus may be used to fill the seal shown in FIGURE 2. in a manner similar to that described in connection with FIGURE 1. As the seal strip is passed through the apparatus shown in FIGURE 1, the knife 39 slits the joining web portion and the bulb portion together with the extension 16A is raised, filled and closed as described in connection with the strip of FIGURE 1. Finally, as the strip portions 16A and 24A are passed between rollers and 46, the diamondshaped wedge 30 is forced into the complementary recess 32 to mechanically lock the parts together as is indicated by the dotted lines. The vertical walls 34 and 36 of the seal base maintain the base 10A and extension 16A in vertical alignment so that as these parts are pressed together between the rollers 45 and 46, the wedge 30 readily enters the groove 32. The parts are then heat sealed as before to provide a permanently sealed joint. Alternatively, the heat sealing step may be eliminated and means may be provided to coat the surfaces of the wedge 30 and/or the recess 32 with a suitable solvent such as tetrahydrofuran in the case of vinyl seal strips to cause the parts to fuse together after being pressed together by non-energized rollers 45 and 46. Providing interlocking means as described above made possible the use of any suitable elastomeric material such as natural and synthetic rubbers for use as the strip material together with suitable solvents and cements.

Another form of the invention is illustrated in FIG- URES 6-10 wherein the seal strip body is slit longitudinally and more or less centrally thereof, and after the filler strip is inserted in place, the base portion is reunited by heating the slit edges by means of an electrical heating element and bringing the edges together in a softened condition by suitable guides and permitting them to fuse together.

In this form of the invention, a seal strip body member 48, shown in FIGURE 7 in cross section, is extruded having a base portion 49 preferably weakened along a longitudinal plane 50 centrally thereof and having a bulb portion 51 and an L-shaped portion 52. This seal strip may be filled with a filler strip utilizing the apparatus shown in FIGURES 6 and 10 wherein the strip, in an inverted position, is moved from top to bottom in FIG- URE 6 and from left to right to FIGURE 9.

Referring to FIGURE 10, the apparatus includes a pair of horizontally disposed, vertically spaced longitudinal guide bars 53 and 54, supported by bracket means 55 supported by base plate 56 which also supports a pair of spaced support members 57. At one end of the guide bars is a knife member 58 suspended between guide bars 53 and 54 and preferably attached thereto at an angle as shown in FIGURE 10 to facilitate its cutting action. The apparatus is shown in FIGURE 6 having the seal strip 48 associated therewith in a filler strip inserting operation. The strip 48 is inserted over the lower guide bar 54 in an inverted position whereby the lower guide bar serves as a support for the seal strip base 49 as shown more clearly in FIGURE 8. As the strip is moved downwardly in FIGURE 6, the seal strip base 49 is slit open as shown in FIGURE 7.

Ahead of the knife member 58, as indicated at 59 (FIGURE 10), the guide members 53 and 54 are joined in a unitary section thereof which has an opening 60 therethrough shown by dotted lines, having a tube 61 secured therein for feeding a filler strip 63 into the seal cavity. The unitary section 59 is externally formed to have a wedge-like guide portion 62 operative to spread apart the slit edges of the seal strip as it passes thcreacross and an opposed wedge-like guide portion 64 permitting the slit edges of the seal strip to be brought together a sufiicient amount to enable the heating element 66 supported by bracket member 68 attached to the support member 57, to soften the slit edges of the strip as shown in FIGURE 9. To this end, the terminals 67 are connected to a suitable source of electrical energy to cause the element 66 to be heated to an adequate degree. After the edges of the strip are adequately softened, they are brought together and fused on cooling. The bringing together of the strip edges is effected by an external guide member 70 as shown in FIGURE 6 which is supported for longitudinal adjustment between the support members 57. The guide member 70 is slidably supported between the support members 57 preferably by means of inwardly directed projections 72 which are received in corresponding grooves disposed on the side walls of the guide member 70. As may be seen in reference to FIGURE 10, the guide member 70 is provided with a longitudinal opening 72 therethrough having a lower portion 74 which receives the seal bulb and an upper portion having walls 76 diverging in a vertical plane against which the side portions of the base of the seal are brought to bear. The mouth of the opening 72 is of a greater dimension than the normal dimension of the seal and the side walls of the opening gradually converge toward the opposite end of the guide member to the final dimension of the eal strip. To effect the sealing of the seal strip base, the guide member 70 is moved to receive the guide bars 53 and 54 into a position shown in FIGURE 6, so that the mouth of the opening 72 is in close proximity to the heating element 66 whereby the heated seal edges are brought together by the guide member 70 as soon as they are adequately softened. In both the apparatus shown in FIGURES 3 and 6, the seal strip is pulled through the apparatus by suitable means and is conveyed to and away from the apparatus by suitable conveyor means. Such means may suitably be a pair of opposed pressure rollers, engaging therebetween the vertical portion of the L-shaped portion of, for example, the strip shown in FIGURE 1, whereby the filled seal strip is not distorted in the pulling thereof through the apparatus. The filler strip 42 of FIGURE 3 and 63 of FIGURE 6 is preferably held within the seal strip body by friction after being laid therein and as the seal body is pulled through the apparatus, the seal strip filler is pulled into place in an obvious manner.

The seal strips contemplated in the present invention are preferably of the heat scalable vinyl types capable of forming, preferably by extrusion, a thin highly flexible bulb portion. An example of a suitable material may include 42.46% polyvinyl chloride, 16.89% precipitated calcium carbonate as a filler, 1.28% barium-cadmium laurate as a heat and light stabilizer, 0.22% stearic acid as a lubricant, 36.94% polyester type plasticizer and 2.12% epoxy resin type plasticizer. The specific material involved in the present invention forms no part of the present invention, the above example being intended merely to show the type of material which may be used.

The filler strip material 42 of FIGURE 3 or 63 of FIGURE 6 may be any mildly resilient material having a capacity to sustain itself in strip form whereby it may be fed into the apparatus by a movement of the seal strip body. Examples of suitable materials include Fiberglas or rock Wool batt in strip form reinforced by a strip of fabric adhesively attached to the base thereof, or by a layer of suitable adhesive applied to the base thereof and cured. The filler strip may also be a low density elastomeric foam or a semi-rigid or flexible low density type foam. The invention also contemplates feeding a foamable polyisocyanate type mixture of the type disclosed in the US. Patent 2,764,565 by means of apparatus of the type disclosed therein. In this case, the tube 61 of FIG- URE 6 and funnel 43 are suitably modified to include suitable nozzle means operative to deposit a stream or ribbon of foamable material in predetermined quantities in the seal cavity which will foam in situ to provide a filler preferably substantially filling the cavity. For this purpose, the embodiment shown in FIGURE 3 is preferred since it involves depositing the tfoarnable material on the base of the seal body which results in a better distribution of filler within the seal cavity after the filler material has foamed.

While the embodiments of the present invention as herein disclosed constitute preferred forms, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. In a method of making an elongated elastorneric sealing strip comprising, a body portion made of heat scalable material, including a relatively flat base portion of substantial tln'ckness, a relatively thin flexible bulb portion integrally attached to the sides of said base portion and filler material disposed within the bulb portion, the steps comprising, longitudinally slitting the base of said bulb for providing an opening in the base of the seal body longitudinally thereof, progressively laying filler material within the cavity of said bulb through said opening, then bringing the edges of the slit portion at the base of the bulb portion into contacting position and sequentially and progressively heat sealing said edges of the slit portion for reforming said bulb portion and for confining permanently the filler material within said bulb portion.

2. A resilient sealing strip, comprising, an elongated relatively flat base portion of a substantial thickness, a relatively thin walled bulb portion integrally connected longitudinally along one side thereof to said base portion and extending throughout the entire length of said base portion, said bulb portion being normally longitudinally free from said base portion at the other side thereof, an interlock extending longitudinally along the entire extent of said strip and having interfitting portions carried by said free side of said bulb portion and by the adjacent part of said. base portion, said interlock being adapted to interlock the free side of the bulb portion in fixed relation to the base portion, resilient filler material within said bulb portion, and a longitudinally extending heat seal extending the full extent of said interlock.

References Cited in the file of this patent UNITED STATES PATENTS 4,741,443 Slade Dec. 31, 1929 1,972,788 Miller Sept. 4, 1934 2,129,607 Schott Sept. 6, 1938 2,195,046 Best Mar. 26, 1940 2,388,297 Slaughter Nov. 6, 1,945 2,492,566 Geyer Dec. 27, 1949 2,582,022 Feldrnan et al J an. 8, '1952 2,589,766 Bradley Mar. 18, 1952 2,672,177 Werneskog Mar. 16, 1954 2,680,888 Jarrow June 15, 1954 2,700,197 Kesling Jan. 25, 1955 2,732,880 Hawk Jan. 31, 1956 2,739,089 Hageltorn Mar. 20, 1956 2,774,620 Beare Dec. 18, 1956 2,786,241 Garvey et 'al. Mar. 26, 1957 

